Leveraging physics-based and explainable machine learning approaches to quantify the relative contributions of rain and air pollutants to wet deposition.

A quantitative understanding of the roles of rainfall and pollutant concentrations in wet deposition is important because they critically influence terrestrial and aquatic ecosystems. However, their relative contributions to wet deposition, which vary across regions, have not yet been identified. We propose two methods that quantitatively separate the contributions of rain and pollutant concentrations to wet deposition: one is based on simplified equations describing the wet scavenging of pollutants and the other is based on random forest models employing SHapley Additive exPlanations.

Greenhouse warming and anthropogenic aerosols synergistically reduce springtime rainfall in low-latitude East Asia.

Low-latitude East Asia, particularly southern China, has experienced a markedly decreasing springtime rainfall in recent years whereas rainfall trends are weak in mid-latitude East Asia. Details of human influences on this contrasting feature remain uncertain. This study provides a quantification of the relative roles of greenhouse warming and aerosols in the observed spring rainfall trends over East Asia using a state-of-the-art numerical model.

Technical note: AQMEII4 Activity 1: evaluation of wet and dry deposition schemes as an integral part of regional-scale air quality models.

We present in this technical note the research protocol for phase 4 of the Air Quality Model Evaluation International Initiative (AQMEII4). This research initiative is divided into two activities, collectively having three goals: (i) to define the current state of the science with respect to representations of wet and especially dry deposition in regional models, (ii) to quantify the extent to which different dry deposition parameterizations influence retrospective air pollutant concentration and flux predictions, and (iii) to identify, through the use of a common set of detailed diagnostics, sensitivity simulations, model evaluation, and reduction of input uncertainty, the specific causes for the current range of these predictions. Activity 1 is dedicated to the diagnostic evaluation of wet and dry deposition processes in regional air quality models (described in this paper), and Activity 2 to the evaluation of dry deposition point models against ozone flux measurements at multiple towers with multiyear observations (to be described in future submissions as part of the special issue on AQMEII4).

Multiple -acting signals, some weak by necessity, collectively direct robust transport of mRNA to the oocyte.

Localization of mRNAs can involve multiple steps, each with its own -acting localization signals and transport factors. How is the transition between different steps orchestrated? We show that the initial step in localization of mRNA - transport from nurse cells to the oocyte - relies on multiple -acting signals. Some of these are binding sites for the translational control factor Bruno, suggesting that Bruno plays an additional role in mRNA transport.

RNA sequences required for the noncoding function of oskar RNA also mediate regulation of Oskar protein expression by Bicoid Stability Factor.

The Drosophila oskar (osk) mRNA is unusual in having both coding and noncoding functions. As an mRNA, osk encodes a protein which is deployed specifically at the posterior of the oocyte. This spatially-restricted deployment relies on a program of mRNA localization and both repression and activation of translation, all dependent on regulatory elements located primarily in the 3' untranslated region (UTR) of the mRNA.

oskar RNA plays multiple noncoding roles to support oogenesis and maintain integrity of the germline/soma distinction.

The Drosophila oskar (osk) mRNA is unusual in that it has both coding and noncoding functions. As an mRNA, osk encodes a protein required for embryonic patterning and germ cell formation. Independent of that function, the absence of osk mRNA disrupts formation of the karyosome and blocks progression through oogenesis.

Lipoteichoic acid from Lactobacillus plantarum induces nitric oxide production in the presence of interferon-γ in murine macrophages.

Lipoteichoic acid (LTA) is a major immuno-stimulating component of Gram-positive bacteria. LTA from the beneficial bacterium Lactobacillus plantarum induces weak nitric oxide (NO) production in murine macrophages. Currently, it is not clear if LTA from L.

dFMRP and Caprin, translational regulators of synaptic plasticity, control the cell cycle at the Drosophila mid-blastula transition.

The molecular mechanisms driving the conserved metazoan developmental shift referred to as the mid-blastula transition (MBT) remain mysterious. Typically, cleavage divisions give way to longer asynchronous cell cycles with the acquisition of a gap phase. In Drosophila, rapid synchronous nuclear divisions must pause at the MBT to allow the formation of a cellular blastoderm through a special form of cytokinesis termed cellularization.

Recognition of lipopeptide patterns by Toll-like receptor 2-Toll-like receptor 6 heterodimer.

Toll-like receptor 2 (TLR2) initiates potent immune responses by recognizing diacylated and triacylated lipopeptides. Its ligand specificity is controlled by whether it heterodimerizes with TLR1 or TLR6. We have determined the crystal structures of TLR2-TLR6-diacylated lipopeptide, TLR2-lipoteichoic acid, and TLR2-PE-DTPA complexes.

Bacillus anthracis lethal toxin attenuates lipoteichoic acid-induced maturation and activation of dendritic cells through a unique mechanism.

Lethal toxin (LT), produced by the gram-positive bacterium Bacillus anthracis, was identified as a major etiologic agent causing anthrax due to its strong immunotoxicity. Gram-positive bacteria express lipoteichoic acid (LTA), which is considered as a counterpart to lipopolysaccharide (LPS) of gram-negative bacteria, but differs from LPS in the structure and function. Since dendritic cells (DCs) are essential for the appropriate initiation of immune response, we investigated the effect of LT on LTA-induced DC maturation using immature DCs prepared by differentiation of C57BL/6 mouse bone marrow cells.

Impaired osteoclastogenesis by staphylococcal lipoteichoic acid through Toll-like receptor 2 with partial involvement of MyD88.

Degenerative bone disease, marked by excessive loss of calcified matrix, is often associated with bacterial infections. Osteoclasts, which mediate the bone-resorptive process, are derived mainly from myeloid precursor cells of the monocyte/macrophage lineage, from which cells with phagocytic and inflammatory capacities may alternatively arise. Here, we investigated the effect of LTA, a major cell-wall virulence factor of Gram-positive bacteria, on osteoclast differentiation.

Differential immunostimulatory effects of Gram-positive bacteria due to their lipoteichoic acids.

Lipoteichoic acid (LTA) is a major immunostimulating component in the cell wall of Gram-positive bacteria as lipopolysaccharide of Gram-negative bacteria. However, LTA is expressed on not only pathogenic but also nonpathogenic Gram-positive bacteria. In order to examine whether the immunostimulating potentials of Gram-positive bacteria are correlated with their LTAs, we prepared highly pure LTAs from Staphylococcus aureus (pathogenic), Bacillus subtilis (non-pathogenic), or Lactobacillus plantarum (beneficial).

A food-born heterocyclic amine, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), suppresses tumor necrosis factor-alpha expression in lipoteichoic acid-stimulated RAW 264.7 cells.

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a heterocyclic amine with strong carcinogenic and mutagenic potential, is created abundantly in the overcooking of meat and fish. Carcinogenic toxicants are often implicated in immunosuppression, where cancer cells are not easily eliminated by the host immune system. Here, we investigated the effect of PhIP on tumor necrosis factor-alpha (TNF-alpha) expression by murine macrophage-like cells (RAW 264.

Lipoteichoic acid partially contributes to the inflammatory responses to Enterococcus faecalis.

Enterococcus faecalis, a pathogenic gram-positive bacterium, is closely related to refractory apical periodontitis. Because lipoteichoic acid (LTA) is considered a major virulence factor of gram-positive bacteria, in the present study, highly pure LTA from E. faecalis was prepared, and its ability to stimulate murine macrophages was investigated in comparison with those of the killed whole cells.

Endotoxin contamination in commercially available pokeweed mitogen contributes to the activation of murine macrophages and human dendritic cell maturation.

Commercially available pokeweed mitogen (PWM) has been reported to activate macrophages, leading to production of proinflammatory cytokines and nitric oxide (NO). However, we found that polymyxin B (PMB), a specific inhibitor of endotoxin activity, inhibited the PWM-induced expression of proinflammatory cytokines and NO and the activation of Toll-like receptor 4 (TLR4). A kinetic-turbidimetric Limulus amebocyte lysate assay demonstrated that commercial PWM contained substantial endotoxin, over 10(4) endotoxin units/mg of the PWM.

Comparison of proteome between hepatitis B virus- and hepatitis C virus-associated hepatocellular carcinoma.

Purpose: Hepatocellular carcinoma (HCC) is one of the most common malignant cancers closely associated with chronic infection by the hepatitis B virus (HBV) or the hepatitis C virus (HCV) throughout the world. Differential expression of the proteome in HBV- and HCV-associated HCC was investigated to identify any useful biomarkers indicating virus-specific hepatocarcinogenesis.

Experimental Design: Twenty-one pairs of specimens (tumorous and surrounding nontumorous liver tissues) were obtained from 21 HCC patients.